JPH0648178B2 - Optical axis adjusting device and optical axis adjusting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a one-dimensional optical sensor that receives incident light and scattered light, particularly when the diameter of a dropped droplet is measured and detected by scattered light from the droplet. The present invention relates to an optical axis adjusting device and an optical axis adjusting method for an incident optical axis and a light receiving axis used for determining mutual arrangement.

<Prior Art> Japanese Patent Application Laid-Open No. 63-19506 describes a method for remotely and accurately measuring the size of a dropped droplet. This method
Collimated light is made incident on the dropped droplet, and scattered light composed of reflected light and transmitted refracted light scattered from the droplet at a predetermined scattering angle is imaged on a one-dimensional optical sensor by an optical imaging system. A method of detecting the diameter of the droplet from the distance between two bright spots formed in the image by the reflected light and the transmitted refracted light and the magnification of the optical imaging system. In this method, the angle for detecting scattered light can be set arbitrarily, but regardless of the size of the angle, this angle is set accurately in order to accurately detect the diameter of the dropped droplet. There is a need to.

Conventionally, in order to accurately set the angle for detecting the scattered light, in addition to the devices and parts necessary for detecting the diameter of the dropped droplet, such as a parallel light source, an optical imaging system, and a one-dimensional optical sensor, A beam source such as a new laser oscillator, a reflecting mirror, a reference scale, a fluorescent lamp, and a ball lens are used to determine the arrangement of the parallel light source and the one-dimensional sensor for the droplet to be detected in the following procedure.

′. As shown in FIG. 1, the beam light source A is installed with respect to the parallel light source 10 at a position where the optical axes of the emitted lights intersect at a predetermined intersection angle θ. Usually, the beam light source A is installed on a stable table such as an optical bench.

′. The light receiving surface of the one-dimensional optical sensor 20 and the light emitting surface of the beam light source A are installed so as to face each other, and the optical axes thereof are aligned with each other.
It is confirmed that this optical axis alignment is completed when the beam reflected light from the optical system (for example, a filter or the like) arranged between the one-dimensional optical sensor 20 and the beam light source A matches the beam incident light.

′. A reflector is rotatably attached to the center of the detection area,
The rotation axis supporting vertically is arranged, the reflecting surface of this reflecting mirror and the light emitting surface of the beam light source A are opposed to each other, the radiation optical axis of the beam light source A and the rotation axis supporting the reflecting mirror intersect, and the beam reflection Adjust the reflector so that the light matches the beam incident light. Then, the light emission of the beam source A is stopped.

′. Place the reflector on the left side, that is, on the side of the parallel light source 10 (π / 2
Accurate rotation by + θ / 2). (This rotation causes the light emitting surface of the parallel light source 10 and the light receiving surface of the one-dimensional photosensor 20 to face each other via the reflecting surface of the reflecting mirror.

′. The optical axis of the central portion of the light beam emitted from the parallel light source 10 (hereinafter abbreviated as the central optical axis) and the optical axis of the one-dimensional optical sensor 20 are aligned with each other via the reflecting surface of the reflecting mirror. For this optical axis alignment, for example, a plate with a hole of about 1 mmφ is arranged so that the central optical axis of the parallel light source 10 penetrates this hole, and the one-dimensional optical sensor 20 in front of this central optical axis-shaped light beam By moving the parallel light source 10 or the one-dimensional optical sensor 20 so that the reflected light from the optical system (for example, the filter) matches the beam incident light and the reflected beam spot is not seen on the aperture plate. Done.

′. In place of the reflecting mirror, a reference scale having an opening with a constant diameter, for example, 10 μmφ is arranged, light is emitted from the beam light source A, and the light beam output detected by the one-dimensional photosensor 20 through the opening is maximum. Adjust the position of the reference scale so that

′. A fluorescent lamp is used instead of the beam light source A, and the fluorescent lamp illuminates the one-dimensional optical sensor 20 through the reference scale, and the light pattern from the aperture of the reference scale is located at the central position of the one-dimensional optical sensor 20. The one-dimensional optical sensor is moved laterally as detected by.

′. A ball lens is installed in place of the reference scale, the ball lens is illuminated by the parallel light source 10, and the one-dimensional optical sensor 20 that receives scattered light from the ball lens maximizes the amount of received light. Both of the optical sensors are moved up and down by about 10 μm within the range, and fixed when the light beam output detected by the one-dimensional optical sensor 20 shows the maximum value.

<Problems to be Solved by the Invention> As described above, in order to accurately set the angle at which the scattered light of the dropped droplet is detected, a beam light source, a reflecting mirror, a reference scale, a fluorescent lamp, a ball lens, etc. Many optical devices and optical components have been used to mutually arrange one-dimensional photosensors that receive incident light and scattered light from a parallel light source.

Further, the adjustment of the optical axes of the incident optical axis and the light receiving axis for determining the device requires the complicated procedure as described above, and therefore, even if the skilled person succeeds in the adjustment only once, it takes nearly two hours. It was a half-day job in the normal case where readjustment etc. was required.

Therefore, the present invention has a small number of optical devices and optical components, and an optical axis adjusting device and an optical axis for an incident optical axis and a light receiving axis that allow even an amateur to easily set, for example, the angle at which a dropped liquid droplet is accurately detected by a simple procedure. The purpose is to provide a method of adjustment.

<Means for Solving the Problems> According to the present invention, the incident light axis of refracted light and the optical axis alignment of the light receiving axis have a triangular prism shape having an isosceles triangular cross section surrounded by two light transmitting planes having the same reflecting planes. Alternatively, a trapezoidal reflector excluding the non-isogonal portion and a support for the reflector facing the one light transmitting plane, and vertically incident on another light transmitting plane exposed to the outside, the reflecting plane A partition plate having an opening through which the light reflected by the plate passes, a partition shaft that vertically supports the partition plate, and a positioning mechanism that positions the partition plate by rotating and moving the partition shaft vertically and horizontally. Using the optical axis adjusting device provided, this optical axis adjusting device is arranged so that the screen axis is located substantially at the refraction point of the refracted light, and the screen is rotated to make the incident light incident on the reflector. The light is incident vertically on the light transmission plane exposed to the outside, This is achieved by arranging the light reflected by the reflecting plane of the reflector to pass through the opening of the partition plate, and then aligning the light passing through the opening of the partition plate with the optical axis of the light receiver.

The triangular prism or the trapezoidal reflector is, for example, a triangular prism reflector in which a prism or a reflecting mirror and two glass plates are adhered to each other, or a path for refracted light when the optical axes are aligned from the reflectors by the above method. An example is a columnar reflector without the unequal angle of a triangular prism.

Further, between the reflector and the collision plate, it is preferable to adjust the light amount by interposing a light-shielding plate having a pinhole or a slit opening, a dimming device such as a gray filter,
As a result, it is possible to prevent damage to the light receiver caused by excessive intensity of light received, and obtain the same effect as the adjustment using the reference scale that is performed in the conventional method.

Further, when the light transmission plane exposed to the outside of the triangular prism or the trapezoidal reflector is a half mirror, the incident light is partially reflected on this surface, so that the same light amount adjustment as described above is performed, and conventionally, It is not necessary to use the reflecting mirror required for adjusting the incident optical axis.

<Operation> According to the configuration of the present invention described above, the partition axis in the optical axis adjusting device is located substantially at the refraction point of refracted light, and the intersection angle of the two transmission planes of the triangular prism or the trapezoidal reflector is the refraction angle. Correspondingly, the optical axes of the incident light axis and the light receiving axis of the refracted light are easily adjusted by rotating the partition shaft by the positioning mechanism and moving up and down and laterally.

<Example> Hereinafter, the present invention will be described more specifically with reference to the accompanying drawings.

FIGS. 2A and 2B show an example of the optical axis adjusting device of the present invention. The optical axis adjusting device 30 has a number of one-dimensional optical sensors 20 corresponding to the diameters of the dropped droplets in a plurality of detection areas. Is for arranging the parallel light source 10 and the plurality of one-dimensional photosensors 20 for simultaneous measurement by means of a plurality of prisms 1, and the same number of openings a as the prisms 1 are laterally separated by a predetermined distance. It is provided with a light-blocking partition plate 2 provided, a partition shaft 3 for vertically supporting the partition plate 2, and a positioning mechanism 4 for positioning the partition plate 2 by rotating and moving the partition shaft 3 vertically and horizontally. ing. Of these, the prism 1 is a triangular prism having an isosceles triangular cross-section as shown in FIG. 3, and one of two identical column surfaces covers the opening a of the partition plate 2 to form the partition plate 2. The prism 1 and the partition plate 2 are supported, and a parallel gap is provided between the prism 1 and the partition plate 2 for inserting and removing the dimmer 5.

Further, a half mirroring treatment coating is provided on the outer cylindrical surface of the prism 1.

When the arrangement of the parallel light source 10 and the one-dimensional optical sensor 20 of the dropped droplet detecting device described above is determined by the optical axis adjusting device 30 ,. First, as shown in FIG. 4, the optical axis adjusting device 30 is arranged so that the partition shaft 3 is located substantially at the center of the detection area.

． Then, as shown in FIG. 3, one of the prisms 1 supported by the partition plate 2, for example, the prism 1 on the partition shaft 3 and a light-shielding plate 6 having a pinhole are provided between the parallel light source 10 and the prism 1. The central optical axis beam is applied to the prism 1.

． After that, as shown in FIG. 2A, the partition shaft 3 is rotated by the positioning mechanism 4, and the partition shaft 3 is vertically moved and moved laterally so that the central light beam is perpendicular to the outer cylindrical surface of the prism 1. Inject the axial beam. When the reflected beam spot is hardly projected at all on the light shielding plate 6 and the reflected beam matches the incident beam, it is determined that the incident optical axis adjustment is completed.

． Finally, the dimmer 5 is placed in the gap between the prism 1 and the partition plate 2 and refracted in the prism 1 to open the opening a of the partition plate 2.
The central optical axis beam emitted from the optical axis and the optical axis of the one-dimensional optical sensor 20 are aligned with each other. This procedure is similar to that of the conventional method described above. At this stage, the conventional method ',
The same adjustment as the adjustment using the reference scale performed in ′ ′ is performed, and the parallel light source 10 and the one-dimensional light in which the maximum light amount position obtained by finely adjusting the one-dimensional optical sensor 20 in the vertical direction is adjusted. This is the arrangement position of the sensor 20.

<Effects of the Invention> As described above, by using the optical adjustment device of the present invention, a beam light source, a reflecting mirror, and
Without using a reference scale, a fluorescent lamp, a ball lens, etc., the optical axis adjustment can be completed easily and accurately by an amateur within a few minutes. Therefore, according to the present invention, the incident optical axis of refracted light and The optical axis adjustment time of the light receiving axis can be significantly shortened.

[Brief description of drawings]

FIG. 1 is a drawing for explaining a conventional optical axis adjusting device and an optical axis adjusting method, FIG. 2A is a perspective view showing the optical axis adjusting device of the present invention, and FIG. 2 is FIG. 2A. FIG. 3 is a drawing schematically showing a main part of the optical axis adjusting device, FIG. 3 is a drawing for explaining the optical axis adjusting method of the present invention, and FIG. 4 is an optical axis adjusting of the present invention at the time of adjusting the optical axis. FIG. 2 is a partially enlarged view of FIG. 2B showing a path of light passing through the device. 1 ... Prism, 2 ... Partition plate, 3 ... Partition axis, 4 ...
Positioning mechanism, 5 ... Dimmer, 6 ... Shading plate, 10 ...
Parallel light source, 20 ... One-dimensional optical sensor, 30 ... Optical axis adjusting device, A ... Beam light source, a ... Aperture.

Claims (4)

[Claims] 1. A trapezoidal reflector having an isosceles triangular cross section surrounded by two light transmitting planes whose reflection planes are equal to each other or a trapezoidal reflector excluding the non-isogonal portion thereof, and the reflector being one light transmitting plane thereof. A partition plate having an opening through which the light which is faced and supported and which is vertically incident on another light-transmitting plane exposed to the outside and which is reflected by the reflection plane pass through, and a partition shaft which vertically supports the partition plate. An optical axis adjusting device comprising: a positioning mechanism that positions the partition plate by rotating the partition shaft and moving the partition shaft vertically and horizontally. 2. An apparatus according to claim 1, wherein a dimmer is interposed between the triangular prism or trapezoidal reflector and the collision plate. 3. The light-transmitting plane exposed to the outside of the triangular or trapezoidal reflector is a half mirror.
The described device. 4. The optical axis adjusting device according to any one of claims 1 to 3, wherein the optical axis adjusting device is arranged so that the screen axis is approximately located at a refraction point of refracted light. By rotating the partition plate, the incident light is vertically incident on the light transmitting plane exposed to the outside of the triangular prism or the columnar reflector, and the light reflected by the reflecting plane of the triangular prism or the columnar reflector is the partition plate. An optical axis adjusting method, which is arranged so as to pass through the opening, and after that, the light passing through the opening of the partition plate and the optical axis of the light receiver are aligned.